Background of Invention:
In the realm of organic chemistry, organic synthesis reigns supreme as the most fascinating area of activity. The demand for new chemicals spanning the fields of healthcare to materials combined with the pressure to produce these substances in an environmentally benign fashion pose great challenges to the synthetic chemical community. The maximization of synthetic efficiency by the conversion of simple building blocks into complex targets remains a fundamental goal. The synthetic community has been put under increased pressure to produce, in an environmentally benign fashion, the myriad of substances required by the society. A major goal of this endeavour must be to use raw materials efficiently. Thus, synthetic efficiency has to be addressed not only by selectivity but also economically.
One of such enthusiastic challenges has been in developing controlled generation of well-functionalized three-dimensional structures from simple planar starting materials, as it allows fast access to solve molecular intricacy at higher levels. Dearomatization of abundant arenes is considered to be the shortest and most powerful approach towards the goal.1 This resembles a versatile transformation that has been considered an attractive and straightforward method for the construction of a range of molecular architectures from simple planar starting materials. The main advantage being the possibility of converting an aromatic ring into a three dimensional molecule generating multiple chiral centres in one shot, creating an aromatic C-H activation at the expense of aromatic energy. This not only fulfils the well-judged target of atom-economy but also empowers the scientific community to see through above thermodynamic stability. This would also directly manifest on atom economic dearomatization reactions which would absolutely solve the challenge of one-pot aromatic C-H activation for future use. (Fig-1)
Readily available phenols, anilines, naphthols, indoles, pyridines are widely used as the primary substrates for oxidative dearomatization reactions delivering functionalized 3D intermediates for further applications.2 (Fig-2)
There has been serious attempts by different groups, throughout the globe on developing
dearomatization techniques. Important complex molecules such as spirone, cycloadduct,
cyclohexadieneone with multichiral centres are target points which can be reached employing
dearomatization as the key reaction step. (Fig-3)
Oxidative Dearomatization till now can mainly be divided into three categories which are as
follows:
♦ Metal free oxidative dearomatization
♦ Transition metal catalysed/metal mediated oxidative dearomatization
♦ Organo-catalytic oxidative dearomatization.

Among these three, the last one i.e. Organo-catalytic oxidative dearomatization reactions exhibit low successful reaction scope. Transition metal catalysed approaches are associated with major drawbacks being expensive and produce toxic metal wastes which warrants a major environment concern. Thus metal free protocols demand for enormous immediate attention towards this magnificent transformation.
The mostly used reagent in the non-metal category has been hypervalent iodine complexes which has readily resulted onto uncontrollable dearomatization reactions leading to dimers and unwanted by-products. (Fig-4)
Hypervalent iodine complexes are synthesised under rigorous conditions in presence of drastic oxidising agents like sulphuric acid and potassium bromate. Again, the utmost significance of these complexes in dearomatisation reaction and drawbacks like not being generalizable, scalable, non-economic and creating metal-free environment associated with all such processes has put us an urge for exploring newer simplified pathways of this reaction.
Statement of Invention:
The present invention discloses the effectiveness of a less explored Phenyl trimethyl ammonium tribromide (PTAB) and related tribromides as important reagents towards oxidative dearomatization reactions. Till now oxidation capacities of PTAB or rather "tribromides" have been rarely explored. These poly-halides have been primarily employed as brominating agents.4 Apart from the lack of generalizability with available metal free protocols associated with oxidative dearomatization, the mechanistic uncertainty3 involved with these class of reactions prompted us to pursue the studies with a new reagent.
Mechanistic uncertainty:
Harned in his review3 highlighted two mechanisms being effective for oxidative dearomatizations one of which is associative and the other one is dissociative which keep this as a subject of debate.
Selectivity:
The selectivity encountered is also very less in case of hypervalent mediated oxidative dearomatization reactions. Possibilities of forming mixture of products during the reaction depending on the substrate profile as well as the reagent profiles has been common observation.

Dimerization has been a common unwanted reaction in case of dearomatization. (Fig 5)
Along with these, the preparation of the hypervalent iodine required very harsh reaction condition as well as hazardous reagents like sulphuric acid, potassium bromate, trifiuoroacetic acid, acetic acid , acetic anhydride etc. Also, the hypervalent iodine could not be employed in presence of active free alcohols because alcohols are oxidized very faster compared to anti-thermodynamic dearomatization reactions. So the reactions were neither scalable nor environmental friendly.
The utmost significance of these complexes in dearomatization reactions and associated drawbacks like not being generalizable, scalable, non-economic and creating metal-free environment associated with all such processes has put us an urge for exploring newer simplified pathways of this reaction. Undoubtedly, the chemist community has no generalised and judicious alternative to dearomatization till now.
Dearomatization of planar aromatics and development of its simple version have one of the unique interests of our group. So the entire work describes new and generalized approach towards oxidative dearomatization reactions. (Fig 6)
The present invention has been summarised in the following two points:
a)PTAB mediated facile generation of oxa-spirocycles.
b)PTAB mediated One-pot Metal free Oxidative Amination, Azidation and Peroxidation of
Phenols.
Object of Invention:
There has been continued interest in performing oxidative dearomatization reactions using hypervalent iodine mediated oxidation,6 metal-arene complexation7 and organocatalysis,8 where a stoichiometric amount of metal complex or oxidant is required. Hypervalent iodine reagents have significantly drawn attention due to their high oxidising properties, chempselectivity and environment acceptability. A closer and extensive literature survey on the natural product synthesis using oxidative dearomatization fetches an impression that only hypervalent iodine complexes have been utilized as an effective reagent for dearomatization in wide scale natural product syntheses.10 Hypervalent iodine complexes are synthesised using harsh conditions in presence of highly oxidising agents like potassium bromate and sulphuric acid. Also, it has been associated with drawbacks like not being scalable, generalizable, required rigorous reaction conditions and non-economic. Metal-mediated reactions generate toxic metal waste and transition metal has been dwelling with a tag of being non-economic. Undoubtedly, the chemist community has been looking for generalized & economic protocols to dearomatize planar arenes.

Upon dearomatization, aromatic and heteroaromatic derivatives deliver highly reactive intermediates which lead to facile C-C bond and C-heteroatom bond formation. Spirocyclic structural motifs remain an interesting area of attraction for organic chemists all over the world due to their challenging stereochemistry, immense biological activity and wide scale application aschiral ligands."
Firstly, a generalised economic way-out for brominative oxidative dearomatization of naphthols and the first synthesis of a wide variety of spiro-oxacyles (spiro-etherification, spirolactonisation) from planar naphthols is achieved. A convincing range of diasteroselective spiro-furan-naphthalone generation, overall fantastic yields, rich substrate scope, mild conditions along with the economy involved, makes this a sustainable one. (Fig 7)
Secondly, aminocyclohexadieneones, azido-napthaleneones and peroxo-cyclohexadieneones constitute the central core for a vast set of medicinally important molecules and thus create an extreme focus of attention. Except the conventional procedure of a-amination of carbonyl compounds nucleophilic oxidative dearomatization can be used for generation of amino-carbonyl compound as well as peroxy-carbonyl compound starting from simple phenol and naphthols. (Fig-8).Interestingly extensive literature survey has fetched us scanty reports focussing on discrete available for stereoselective amination, azidation and peroxidation of phenols and naphthols using oxidative dearomatization to generate the corresponding cyclohexadieneone and naphthlones.
In this invention, we also report a unique and simplest "trio" of aminative, azidative and peroxidative dearomatization of phenols and naphthols. The generalisability, wider substrate scope, huge functional group tolerance and the associated simplicity of the reaction conditions makes this strategy first of its kind. The facile generation of a quaternary centre with amine, azide and the peroxide substitutions from easily available phenolics, labile functional group tolerance has given a special attention to this synthetic protocol. Above all, it supersedes all the existing discrete methodologies being not limited only to naphthols rather is applicable to the entire phenolic community along with labile functionalities. The diverse range of amino, azido and peroxo-cyclohexadieneones as well as naphthalones synthesised in one pot can be easily extended towards generation of synthetically important heterocyclic motifs, thus solving molecular intricacy to greater extents.

SUMMARY OF INVENTION
The invention describes the first recognition of Phenyl Trimethyl Ammonium Tribromide (PTAB) as an effective reagent for halogenative dearomatization as well as oxa-spirocyclization proceeding via oxidative dearomatization. The experiment exhibits economic, metal and ligand free one-pot accomplishment of these significant transformations. The described protocol presents the first generalised methodology of spiro-oxacycle synthesis which can be applied towards various directions. A stereoselective synthesis of oxa-spirocyclooxadieneones has been accomplished.
Concurrently a unique and simplest "trio" of aminative, azidative and peroxidative dearomatization of phenols and naphthols a highly efficient methodology for generation of nitrogen containing quarternary carbon centres via aminative and azidative oxidative dearomatization of phenols. The same protocol has also been succesfully employed to achieve oxidative peroxidation of phenols. The simplest metal free reaction conditions delineates an easy break through to the "trio"- of oxidative amination, azidation and peroxidation. An array of diverse polyfunctionalised heterocycles has been synthesized in one pot.

Figure 1- The figure represents the direct conversion of commonly available arene to functionalized 3d intermediate using oxidative dearomatization as prime step.

Figure 4- The figure represents the possible products from hypervalent iodine mediated oxidative dearomatization reaction.

Figure 5- The figure shows the formation of unwanted dimerization product in hypervalent iodine mediated oxidative dearomatization which is a side-product in such reactions whereas no such dimerization has been observed in tribromide mediated dearomatization.

Figure 7- The figure exemplifies the synthesis of spiro-furano-napthalones, bromo-spiro-furano-napthalones, benzylic bromoketones, spirolactones in the PTAB mediated dearomatization of appropriately substituted phenols.

Figure 8- The figure depicts the developed "Reaction Trio" employing PTAB mediated oxidative dearomatization.

DETAILED DESCRIPTION
TLC was performed with .25mm coated commercial silica gel plates (E-Merck, DC-kiesel gel 60 F254) and stain by Iodine, vanillin solution. Chromatographic separation was done by using (100-200mesh) silica gel.'H & 13C NMR were recorded on a Bruker (400MHz). NMR chemical shift value are reported in ( ppm). TMS taken as internal slandered for 1H the residual signal for CDCI3 taken as 7.28 ppm & for 13C 77.00ppm. 1H spectral data reported as  (multiplicity, Coupling constant, integration). Multiplicity reported as follows, s=singlet, d=doublet, t=triplet, q=quartet, m=multiplate, dd=doublet of a doublet. HRMS (High resolution Mass Spectra) was measured in a QTOF I (quadrupolehexapole-TOF) mass spectrometer with an orthogonal Z-spray-electrospray interface on micro (YA-263) mass spectrometer. IR. spectra were recorded by using Perkin-Elmer spectrum-2 spectrometer using thin film deposit on NaCl & absorption frequency reported in cm'1.
General experimental procedure (A): To a stirred solution of alkyl naphthol (1 equiv.) & K2CO3 ( 1 equiv.) in dry THF (3 ml) at room temperature, PTAB (1 equiv.) was added followed by stirring for 4h, then the reaction mixture was quenched with distilled water and extracted with ethyl acetate (3X3ml). The organic part was washed with brine solution and dried over anhydrous sodium sulphate, followed by removal of the solvent under reduced pressure. Then the reaction mixture was subjected to column chromatography over silica gel.

This reaction was carried out according to the general experimental procedure (A). To a mixture of l-phenethylnaphthalen-2-ol (115 mg, 0.46 mmol) in dry THF & K2CO3 (64 mg, 0.47 mmol),

PTAB (175 mg, 0.46 mmol) was added. The resulting mixture was stirred at room temperature for 8h.The mixture was purified by silica column using 8% EtOAc in petroleum ether (60-80) to give l-bromo-l-phenethylnaphthalen-2(lH)-one (120 mg, 80 %) as yellow liquid. Rr = 0.6 (30% EtOAc in petroleum ether (60-80)).
'H NMR (400 MHz, CDC13)  = 7.84 (d, J = 8 Hz, 1H), 7.512-7,55 (m, 1H), 7.38-7.47 (m, 3H), 7.26-7.29 (m, 2H), 7.18-7.22 (m, 1H), 7.11-7.13 (m, 2H), 6.38 (d, J= 10 Hz, 1H), 3.29-3.72 (m, 1H), 2.95 (td, J' = 4.8 Hz, J2 = 12.8 Hz, 1H), 2.31 (td, J' = 5.2 Hz, J2 = 13.2 Hz, 1H), 2.19 (td, J'= 4.4 Hz, J2=12 Hz, 1H)
13C NMR (100 MHz, CDCI3) = 192.9, 144.1, 140.3, 140.2, 130.8, 130.1, 129.2, 129.1, 128.4, 128.2, 126.2, 124.3, 59.2, 41.0, 32.3. ER (Neat Film, NaCl) 2960, 1670, 1240, 765 cm"1. HRMS (ESI) calc'd for C18H15 BrNaO [M+Na] +: 349.0204, Found 349.0229.

This reaction was carried out according to the general experimental procedure (A). To a mixture of l-(4-methylphenethyl) naphthalen-2-ol (120 mg, 0.45 mmol) in dry THF & K2CO3 (65 mg, 0.47 mmol), PTAB (176 mg, 0.46 mmol) was added. The resulting mixture was stirred at room temperature for 8h. The mixture was purified by silica gel column using 10% EtOAc in petroleum ether (60-80) to give l-bromo-l-bromo-l-(4-methylphenethyl) naphthalen-2(lH)-one (116 mg, 75 %) as yellow liquid. R f = 0.5 (30% EtOAc in petroleum ether (60-80).

1H NMR (400 MHz, CDC13)  = 7.84 (d, J= 8 Hz, 1H), 7.50-7.55 (m, 1H), 7.37-7.46 (m, 3H), 7.08 (d, J= 8 Hz, 2H), 7.01 (d, J= 8 Hz, 2H), 6.38 (d, J 10 Hz, 1H), 3.27-3.35 (m, 1H), 2.92 (td, J'= 4.4 Hz, J2= 12.8 Hz, 1H), 2.32 (s, 3H), 2.23-2.37 (m, 1H), 2.14 (td, J1= 4.4 Hz, J2= 13.2 Hz, 1H).
13C NMR (100 MHz, CDC13)  = 192.8, 143.9, 140.3, 137.1, 135.6, 130.7, 130.0, 129.0, 128.2, 128.0, 124.3, 59.2, 41.1, 31.8, 20.9.
IR (Neat Film, NaCl) 2965, 1672, 1200, 755 cm'1.
HRMS (ESI) calc'd for C19H17BrNaO [M+Na] +: 363.0360, Found 363.0356.

The reaction was conducted according to the general reaction procedure (A). To a stirred mixture
of l-(3-hydroxy-3-methylbutyl) naphthalene-2-ol (70 mg, 0.30 mmol) in dry THF & K2CO3 (42
mg, 0.30 mmol), PTAB (115 mg, 0.30 mmol) was added. The reaction mixture was stirred at
room temperature for 6h. The crude product was purified by silica column chromatography using
10 % EtOAc in petroleum ether (60-80) to furnished 5, 5-dimethyl-4, 5-dihydro-2'H, 3H-spiro
[furan-2, l'-naphthalen]-2-one(52 mg, 76%) as yellow oil.
Rf = 0.7 (20% EtOAc in petroleum ether (60-80)).
1H NMR (400 MHz, CDC13)  = 7.57 (d, J= 7.6 Hz, 1H), 7.28-7.32 (m, 1H), 7.23 (d, J = 9.6
Hz, 1H), 7.15-7.20 (m, 2H), 6.0 (d, J= 9.6 Hz, 1H), 2.38-2.43 (m, 1II), 1,91-1.95 (m, 2H), 1.71-
1.75 (m, 1H), 1.55 (s, 3H), 1.49 (s, 3H).
13C NMR (100 MHz, CDCI3)  = 203.4, 145.6, 143.9, 130.0, 129.7, 128.9, 127.5, 125.2, 123.9,
89.8, 84.7, 40.0, 35.8, 28.0, 28.7;
IR (Neat Film, NaCl) 2967, 1682, 1450, 1056 cm-1.
HRMS (ESI) calc'd for C15H16O2 [M] +: 228.1150, Found 228.1153;


This reaction was carried out according to general experimental condition (A). To a stirred
mixture of l-(3-hydroxybutyl) naphthalene-2-ol (72 mg, 0.33 mmol) in dry THF & K2CO3 (46
mg, 0.33mmol), PTAB (125 mg, 0.33 mmol) was added. The reaction mixture was stirred at
room temperature for 8h. The crude reaction mixture was subjected to column chromatography
over silica gel. Elution with 5% EtOAc in petroleum ether (60-80) afforded two diastereomer
(rS,5S)-5-methyl-4,5-dihydro-2'H,3H-spiro[furan-2,1-naphthalen]-2'-one (36 mg, 51 %) as
yellow oil & (1'S,5R)-5-methyl-4,5-dihydro-2H,3H-Spiro[furan-2,1 -naphthalen]-2 -one (30 mg,
42%) as a yellow oil. Isolated overall yield 93%.
Rr = 0.6 (20 % EtOAc in petroleum ether (60-80)).
»H NMR (400 MHz, CDCb) of (6a)  = 7.61 (d, J= 7.6 Hz, 1H), 7.32-7.42 (m, 2H), 7.26-7.32
(m, 2H), 6.10 (d, J= 9.6 Hz, 1H), 4.66-4.73 (m, 1H), 2.38-2.45 (m, 1H), 2.14-2.22 (m, 1H),
1.89-1.96 (m, 1H), 1.65-1.74 (m, 1H), 1.50(d, 7= 6 Hz, 3H).
13C NMR (100 MHz, CDC13)  = 204.2, 145.3, 144.6, 130.0, 129.4, 129.0,.127.6, 125.3, 123.9,
88.0,78.8,40.5,31.8,20.9.
IR (Neat Film, NaCl) 2928, 1683, 1420, 1061 cm"1.
HRMS (ESI) calc'd for C14H14O2 [M] +: 214.0994, Found 214.0996;
1H NMR (400 MHz, CDCI3) of (7a)  = 7.59 (d, J= 8 Hz, 1H), 7.38-7.40 (m, 1H), 7.31-7.35 (m,
1H), 7.25-7.29 (m, 2H), 6.1 l(d, J= 9.6 Hz, 1H), 4.64-4.72 (m, 1H), 2.48-2.53 (m, 1H), 2.03-2.09
(m, 1H), 1.87-1.97 (m, 2H), 1.55 (d,7= 6 Hz, 3H).
13CNMR (100 MHz, CDCb)  = 202.8, 146.0, 144.1, 130.2, 129.5, 128.9, 127.6, 125.3, 123.9,
88.5,79.7,41.2,31.3,20.7.


This reaction was performed following the general experimental condition (A). To a stirred
solution of l-(3-hydroxy-3-phenylpropyl) naphthalene-2-ol (80 mg, 0.29 mmol) in dry THF &
K2CO3 (40 mg, 0.29 mmol), PTAB (108 mg, 0.29 mmol) was added. The crude reaction mixture
was subjected to column chromatography over silica gel using 6% EtOAc in petroleum ether
(60-80) delivered (1S,5R)-5-phenyl-4,5-dihydro-2'H,3H-spiro[furan-2,1-naphthalen]-2-one
(41 mg, 51%) & (1S,5S)-5-phenyl-4,5-dihydro-2'H,3H-spiro[furan-2,1-naphthalen]-2'-one (24
mg, 30%) as a yellow oil. Overall yield 81%.
Rr = 0.55 (20 % EtOAc in petroleum ether (60-80)).
1H NMR (400 MHz, CDCI3) of (55(d))  = 7.87 (d, J = 7.6 Hz, 1H), 7.56-7.73 (m, 2H), 7.37-
7.46 (m, 4H), 7.30-7.37 (m, 3H), 6.17 (d, 7= 10 Hz, 1H), 5.67 (t, J= 6.4 Hz, 1H), 2.53-2.61 (m,
2H), 2.07-2.15 (m,2H).
13C NMR (100 MHz, CDCI3) = 203.8, 144.9, 144.8, 141.6, 130.1, 129.4, 129.2, 128.4, 127.8,
127.4, 125.9, 125.6, 123.9, 87.5, 83.5, 40.5, 32.8;
IR (Neat Film, NaCl) 2975, 1687, 1445, 1070 cm-1
HRMS (ESI) calc'd for C19H1602 [M] +: 276.1150, Found 276.1152.

To a stirred mixture of ethyl 3-(2-hydroxynaphthalen-l-yl)propanoate / 3-(2-hydroxynaphthalen-l-yl)propanoic acid (122 mg, 0.5 mmol) in dry THF & K2CO3 (104 mg, 0.75 mmol), PTAB (188 mg, 0.5 mmol) was added. Then the resulting mixture was stirred at room temperature for 14h. After the completion of the reaction, mixture was quenched with dilute ammonium chloride solution and extracted with (3X4ml) EtOAc. The organic layer was washed with brine solution, dried over sodium sulphate, and then concentrated by reduced pressure. The crude mixture was

subjected to column chromatography over silica gel using 70 % EtOAc to delivered 2'H,3H-spiro[furan-2,r-naphthalene]-2',5(4H)-dione from naphthol ester (73 mg, 68%) as a yellow semisolid.
1H NMR (400 MHz, CDC13)  = 7.57 (d, J = 7.6 Hz, 1H), 7.47-7.50 (m, 2H), 7.36-7.43 (m, 2H), 6.19 (d, J= 10 Hz, 1H), 2.81-2.91 (m, 1 H), 2.63-2.71 (m, 2H), 2.09-2.21 (m, 1H). 13C NMR (100 MHz, CDC13) = 197.4, 176.3, 145.9, 140.5, 130.9, 129.6, 129.0, 125.6, 122.4, 85.7, 35.7, 26.5.
IR (Neat Film, NaCl) 1785, 1681, 1170 cm-1. HRMS (ESI) calc'd for C13H10O3 [M] +: 214.0630, Found 214.0648.
General experimental procedure (B): To a well stirred solution of substituted phenols/substituted naphthols (1 eq.) and appropriate nucleophilic nitrogen containing reagent (amine/azide) or TBHP as well as the base (2 eq.) in dry THF, PTAB (1 eq.) was added. The mixture was stirred for 4-12h at room temperature. Then the mixture was quenched with distilled water and extract with ethyl acetate and dried over oven dried sodium sulphate and solvent was removed using rota evaporator. Then the crude reaction mass was subjected to column chromatography over neutral alumina with appropriate solvent (ethyl acetate and petroleum ether) afforded the desired amino-cyclohexadienone/ aminonaphthalone.

To a well stirred solution of 2, 4, 6-trimethylphenol (68 mg, 0.5 mmol) and benzhydrylamine(185 mg, lmmol) in dry THF (5 ml), PTAB (188 mg, 0.5 mmol) was added and stirred for 12h at room temperature. Then the mixture was quenched with distilled water followed by with ethyl acetate (3X5 ml) and dried over sodium sulphate. Solvent was evaporated and the mass was subjected to neutral alumina column, elution with 3% ethyl acetate in

petroleum ether afforded 4-(benzhydrylamino)-2,4,6-trimethylcyclohexa-2,5-dienone as a colourless solid ( 95 mg, 60 %).
Rf = 0.7 in 20 % ethyl acetate in petroleum ether.
1H NMR (400 MHz, CDC13)  = 7.33-7.17(m, 10H), 6.32(m, 2H), 4.66(s, 1H), 1.73(s, 6H), 1.34(s,3H).
13C NMR (100 MHz, CDC13)  =187.0, 150.1, 145.0, 134.4, 128.2, 127.1, 126.8, 63.16, 55.3, 27.4, 15.6;
IR (Neat Film, NaCl) 3345, 1655, 1255, 757 cm-1.
HRMS (ESI) calc'd for C22H23NNaO [M+Na]+: 340.1677 Found :340.1672;


To a well stirred solution of l-butylnaphthalen-2-ol (10 mg, 0.05 mmol) and sodium azide(20 mg, 0.3mmol) in dry THF (3 ml), PTAB (20 mg, 0.05 mmol) was added and stirred for 6h at room temperature. Then the mixture was quenched with distilled water followed by extracted with ethyl acetate (2X3 ml) and dried over sodium sulphate. Solvent was evaporated and the mass was subjected to neutral alumina column, elution with 5% ethyl acetate in petroleum ether afforded l-azido-l-butylnaphthalen-2(lH)-one as a colourless oil (11 mg, 91 %).
Rf= 0.5 in 10 % ethyl acetate in petroleum ether.
1H NMR (400 MHz, CDC13)  = 7.58(d, J= 7.6 Hz, 1H), 7.49-7.33(m, 4H), 6.20(d, J =10 Hz, 1H), 2.15-2.07(m, 1H), 1.97-1.91(m, 1H), 1.23-1.03(m, 4H), 0.8(t, J=4.8 Hz, 3H).
13C NMR (100 MHz, CDCI3) = 199.6, 145.3, 140.5, 130.3, 129.6, 129.5, 128.4, 127.4, 124.2, 70.6,41.5,25.5,22.4,13.6.
IR (Neat Film, NaCl) 2102, 1670, 1261, 753 cm-1.
HRMS (ESI) calc'd for C14H15N3NaO [M + Na] +: 264.1113 Found : 264.1103.

To a well stirred solution of 2, 4, 6-trimethylphenol (68 mg, 0.5 mmol) and sodium azide(160 mg, 2.4 mmol) in dry THF (5 ml), PTAB (188 mg, 1 mmol) was added and stirred for l0h at room temperature. Then the mixture was quenched with distilled water followed by extracted with ethyl acetate (3X3 ml) and dried over sodium sulphate. Solvent was evaporated and the mass was subjected to neutral alumina column, elution with 5 % ethyl acetate in petroleum ether afforded 4-azido-2, 4,6-trimethylcyclohexa-2,5-dienone as a colourless oil (63 mg, 71 %).

Rf = 0.4 in 20 % ethyl acetate in petroleum ether.
1H NMR (400 MHz, CDC13)  = 6.54 (s, 2H), 1.92 (s, 6H), 1.36 (s, 3H).
13C NMR (100 MHz, CDC13)  = 185.7, 142.4, 135.8, 59.8, 25.2, 15.6.
IR (Neat Film, NaCl) 2099, 1650, 1630, 1223, 749 cm-1.
HRMS (ESI) calc'd for C9H11N3NaO [M + Na] +: 200.0800 Found: 200.0810.

Reaction performed following the general experimental procedure (B). Colourless oil; Yield - 90 %.
Rf = 0.5 in 10 % ethyl acetate in petroleum ether.
1H NMR (400MHz, CDCI3)  = 7.68(d, J= 8Hz,lH), 7.50-7.13(m,7H including CDCI3), 7.00(d, J= 7.2Hz,2H), 6.23(d, J= 10Hz,lH), 2.51-2.44(m, 1H), 2.35-2.19(m,2H), 2.09-1.99(m,lH), 1.17(s,9H).
13C NMR (100 MHz, CDCI3)  = 199.1, 144.6, 143.0, 140.7, 130.9, 129.7, 128.9, 128.1, 128.1, 127.8, 127.1, 125.8, 125.7, 84.9, 80.0, 42.1, 28.6, 26.4.
IR (Neat Film, NaCl) 1683, 1185 cm-1.
HRMS (ESI) calc'd for C22H24Na03 [M + Na] +:359.1623 Found: 359.1620.


To a well stirred solution of ethyl 3-(4-hydroxy-3,5-dimethylphenyl)propanoate (50 mg, 0.22 mmol) , Li2CO3 (35 mg, 0.47 mmol) and benzylamine (50 mg, 0.46 mmol) in dry THF (5 ml), PTAB (81 mg, 0.21 mmol) was added and stirred for 12h at refluxing temperature. Then the mixture was quenched with distilled water followed by extracted with ethyl acetate (2X3 ml) and dried over sodium sulphate. Solvent was evaporated and the mass was subjected to neutral alumina column, elution with 30% ethyl acetate in petroleum ether l-benzyl-7, 9-dimethyl-l-azaspiro [4.5] deca-6, 9-diene-2, 8-dione (44 mg, 71 %).
Rf = 0.3 in 15 % ethyl acetate in petroleum ether.
1H NMR (400 MHz, CDCI3)  = 7.26 - 7.13 (m, 5 H), 6.26 (s, 2H), 4.28 (s, 2H), 2.63 (t, J = 8 Hz, 2H), 2.08 (t, J= 8 Hz, 2H), 1.78(s, 6H);
13C NMR (100 MHz, CDC13)  = 185.8, 174.4, 144.2, 137.9, 136.0, 128.6, 128.2, 127.4, 62.0, 44.4, 30.1, 29.31, 15.7.IR (Neat Film, NaCl) 1675, 1645 cm-1.
HRMS (ESI) calc'd for C18H19NO2 [M] +:281.1416; Found: 281.1409

WE CLAIM:
1. The invention first recognises PTAB as an effective reagent for dearomatization.
2. A generalised economic way-out for brominative oxidative dearomatization of naphthols & synthesis of a wide variety spiro-oxacyles from planar naphthols and phenols is achieved
3. Diastereoselective generation of oxa-spirodieneones, convincing range of diasteroselective spiro-furan-naphthalone generation, overall very good yields, rich substrate scope, mild conditions along with the economy involved, makes this a sustainable methodology, the best of the available lot. Importantly the work also reveals no side reactions like polymerisation which are commonly observed in dearomatization reactions and thus makes it a reliable solution.
4. The work manifests a unique and simplest "trio" of aminative, azidative and peroxidative dearomatisation of Phenols.
5. The facile generation of a quaternary centre employing amine, azide and the peroxide nucleophiles from easily available phenolics along with versatile functional group tolerance has given a special attention to this synthetic protocol. Above all, it supersedes all

the existing discrete methodologies being not limited only to naphthols rather is applicable to the entire phenolic community along with labile functionalities.
6. Varied range of ammonium tribromides like PTAB (Phenyl Trimethyl Ammonium Tribromide), TBAB (Tetrabutyl Ammonium Tribromide), DABCOETB (1-benzyl-4-aza-l-azonia-bicyclo [2.2.2] octane tribromide), TEATB (Tetraethyl Ammonium Tribromide), TOATB (Tetraoctyl Ammonium Tribromide), CTAB (Cetyltrimethyl Ammonium Tribromide), TPPETB (Triphenyl Phosphonium Ethyl Tribromide), DPEDTB (1,2-Dipyridinium ditribromide-ethane) have synthesized in our laboratory and the oxidative dearomatisation tendencies are presently being studied.
7. The commercial rates of tribromides would be much less than the presently known oxidation reagents, thus making them the best of the available lot.